A protonated histidine residue in the active site of aspartate transcarbamoylase, ATCase, is thought to be...

A protonated histidine residue in the active site of aspartate transcarbamoylase, ATCase, is thought to be important in stabilizing the transition state of the bound substrate.

A) Sketch a graph showing the pH dependence of the catalytic rate, assuming that this interaction is essential and dominates the pH-activity profile of the enzyme. Provide the biochemical basis for your graph.

B) The ATCase mechanism is known to proceed via an ordered mechanism. Draw a Cleland notation diagram showing how this reaction proceeds. Abbreviate the second substrate as CP. Two products are formed.

Thank you!

Expert Solution

queen_honey_blossom answered 8 months ago

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